Design and construction of jigs and fixtures



J. WHARTON April 23, 1963 DESIGN AND CONSTRUCTION OF JIGS AND FIXTURESFiled Nov. 5, 1959 Z 3 5 8 l 1 H W IM l m r 0 g A Home y United StatesPatent 3,086,293 DESIGN AND CONSTRUCTION OF JIGS ANDv FIXTURES JohnWharton, St.'Albans, England; Alice Mary Wharton, executrix of theestate of said John Wharton, deceased, assignor to Wharton & -WilcocksLimited, Hertford, Englandv Filed Nov. 3, 1959, Ser. No. 850,738 2Claims. (Cl. 33-174) This invention relates to thedesign andconstruction of jigs and fixtures.

In the specification to Patent No. 2,676,413 there is described andclaimed a jig or fixture for use in the manufacture and production ofcomponent elements to accurate dimensions, such jig or fixture beingbuilt up of a mul+ Y tiplicity of interchangeable standard elements eachfurnished with one or more T-slots, or one or more tenonslots, or one ormore tenons or any combination .of T-slots, tenon slots or tenonsadapted to locate and secure the said standard elements relatively to.one another and to a base or to a frame or frames attached to said base,on which they are mounted and securedto form a complete unitarystructure. Among the standard element-s described in the aforesaidspecification is a socalled angle setting unit which comprises twoparts, namely a circular base part having on its lower face a tenon,tenon slot or the like, by means of which it may be secured to a basemember or to other standard elements such as so -called stop elements,which normally playan important part inthe construction of a jig orfixture, and a body part similar in form to a stop element but providedon its inner or under face with a female spigot adapted to receive amalespigot-provided on the base part, the connection between 'the twoparts being such that the body part may be axially rotated with respectto the base part. The base part is provided with graduations around itsperimeter, and a zero mark for setting purposes is provided on the bodypart. In use the two parts are secured together and to a base member 'orother standard element by a bolt .passing centrally through them.-

Rigidity between the base part and the body part depends to a largeextent upon the friction between them and the base member or otherstandard element on which they are mounted, and in some circumstancesthe relative setting of the parts may be disturbed, for example by asudden severe accidental blow. The present invention has for its objectto minimise or obviate this disadvantage and to this end according tothis invention it is proposed to provide means adapted to be secured tothe body part of an angle setting unit and to a base member on which theunit is mounted, either directly or indirectly through the intermediaryof other standard elements, whereby the rigidity of the setting of theparts of the unit is ensured.

Preferred features of this invention will be apparent from the followingdescription and the appended claims.

In the accompanying drawing:

FIGURE 1 shows in plan and in side elevation respectively two typicalapplications of one form of means in accordance with this invention,

FIGURE 2 shows a third application thereof,

FIGURE 3 shows another form of means in accordance with this inventionfor giving a fixed angle setting, and

FIGURE 4 shows yet another form for giving a plurality of differentfixed angle settings.

In FIGURE 1 two angle setting units are shown, each comprising, aspreviously stated, a circular base part 1 and a body part 2. Means forensuring the rigidity of any relative angular setting of these two partscomprises 3,086,293 Patented Apr. 23, 1963- "ice a plate 3 having anelongated slot 4' formed therein. The. plate 3 is 'of generally T-shape,and the head thereof is apertured at each side forv the reception of'bolts5 which are adapted to engage in a T-slot 6 in the side of the.body. part 1 (as is. more .clearly shown .in FIGURE. 2) ,'1 there-. bysecuring the plate Sand body part 1 together.- The plate 3 is securedto, for example, a base plate 7 by means of a bolt 8 passed through theslot 4 and into a .T-slot'9 in the base plate 7. As the aperture 4 iselongated the bolt 8merely' has to be applied .where this aperturecoin-'v cides withjthe T-slot 9 inthe base plate.

To support the plate 3 away from the base plate one or more cylindricalelements 10 may be passed over. the. stem ofthe bolt 8.:

When the .axis' of the angle setting unit is parallel to. the face of,for instance, a base member (see FIGURE 2), the setting of the body part2 may result in. a slotted: plate 3 secured thereto being disposed at anangle to the: face of the base plate 7. To secure the end of the slottedplate in this case a swivel unit ll is provided, this unit having atenon 12 for locating it in a T-slot in the base. plate}. being. firmlysecured thereto by a bolt' 13. A swivel element 14 carried by a fittedpin 15 is provided; with a screwed rod 16 adapted to be engaged in theslot 4 of the plate 3, securing nuts 17 being provided on.the rod forengagingtlrr'eqplate. on opposite sides thereof.

If desired ttwo opposed slotted Plates (as actually shown in :FIGURE 2)maybe secured to the body part 2 of the anglesettingunit, a separateswivel unit 11 being. associated with each.

Insome cases it is proposed to utilise for the body part of an anglesetting unit a stop element 2 as hereinbefore. referred to (see, forexample, FIGURES). In such cases -the.base-part 1 twould have tenonslots 20; as shown (or. tenons), in its upper and" lower faces.v Thetenon-slot inone face-is disposed at:a fixed angle to the tenon slotin-theother face, one serving to locate the. base part 1 with. respectto, for instance, a base plate 7, and the otherservingto locate-the bodypart 2 with respect tozthe-base part 1 With such an arrangement thesetting of the body part 2 with respect to the base. part 1 is, ofcourse, fixed, and to cater. for different angular settings a range ofbase parts would be provided, each with the tenon slots (or tenons) inthe opposed faces thereof at a different angle.

It may not be convenient to provide such a range of base parts coveringall angles that may be required and to reduce the actual numbernecessary for practical requirements modifications are provided as shownin FIG. 4.

With reference to FIGURE 4, the base part may be constituted by twocircular elements, 1, 1 each adapted to receive a common spigot or bush30, the arrangement being such that the two elements can be rotated withrespect to each other about such spigot or bush. Each element of thebase part has a tenon slot 31 on its under face and a tenon slot 32 inits upper face, the angular relationship between the tenon slots in eachelement being varied to a given degree. The elements are adapted to belocated with respect to each other and to, for instance, a base memberby loose tenons 33. The angular relationship between the tenon slots inthe two elements, which is known, enables the body .part 2 of the anglesetting unit to be set at an angle which is in effect an addition orsubtraction of the angles between the tenon slots in the two elements ofthe base part. If desired more than two elements may be used for thebase part.

Instead of a single tenon slot in the upper face thereof each element 11 of the base part may have (as is actually shown) two tenon slots 32,33 crossing at right angles. A series of such elements would each have asingle tenon slot on the lower face thereof, these tenon slots beingarranged at different angles some varying in clockwise direction andsome anti-clockwise. By this arrangement any degree or fraction of adegree setting may be obtained, by the addition or subtraction of theangles represented by a number of base elements.

Thus, for example, a series of individual angle base elements, bothclockwise and anti-clockwise, with angular relationship between tenonslots of /2, 1, 1 /2, 2, 2%", 3, 3 /2", 5, 7 /2 15, 22 /2, 30, 37 withone at 45 will provide any angle from 0 to 45 in /2 increments. In otherwords the total number of such base elements required would betwenty-seven.

The provision of the crossing tenon slots 32, 33 in the upper faces ofthe base elements permit further variations in setting, actuallycovering a full scale from 0 to 360 in /z increments.

With the various arrangements described above rigidity of the setting ofan angle setting unit can be ensured, that is either through theadditional anchorage provided by the slotted plate or plates 3, orthrough the circular base element or elements 1*, 1 1. In the case ofthe latter, a stop element mounted thereon may be interlocked therewithby means of a tenon element 34, adapted to engage in the slot 33 in theupper face of the uppermost base element 1 disposed at right angles tothe slot in which is engaged the tenon 33 on the underside of the stopelement.

I claim:

1. A unit for use in constructing the frame-work of a jig or fixture toposition a work-piece above a base having a flat face formed with aplurality of equally spaced parallel T-slots extending lengthwise in theupper face of the base, which unit comprises interchangeable rings eachhaving a first tenon slot in its underface, tenon means removablyengageable in a T-slot of said base and the first tenon slot of aselected ring for orienting the selected ring with respect to a slot inthe base, each ring also having a second tenon slot in its upper facedisposed at a respective fixed angle to said first tenon slot, the fixedangles of respective rings differing from each other, a block ofpolygonal section adapted to be mounted on the selected ring on the baseand having a flat lower end engageable with the upper face of theselected ring, tenon means operatively associated with said block andengageable in said second tenon slot of the selected ring thereby todetermine fixedly the angular relationship between the block and thering, and means for securing the block and the selected ring to thebase.

2. A unit for use in constructing the frame-work of a jig or fixture toposition a work-piece above a base having a flat upper face formed witha plurality of equally spaced parallel T-slots extending lengthwise inthe upper face of the base, Which unit comprises plural rings eachhaving a tenon slot extending diametrically of its under face and alsohaving a pair of tenon slots extending diametrically of its upper faceperpendicular to each other and at a selected fixed angle to the tenonslot in the under face of the ring, the fixed angles of respective ringsdiffering from each other, tenon means engageable in the tenon slot inthe under face of a first selected ring and in a slot in the upper faceof the base for locating and fixedly orienting a selected first ringwith respect to the base; tenon means engageable in the tenon slot inthe under face or" a second selected ring and in one of the tenon slotsin the upper face of said first selected ring for locating and orientingthe second ring with respect to the first ring, whereby, by properselection of a first and second ring having respective fixed angles, apredetermined orientation between the tenon slots in the upper surfaceof said second ring and the slots in the upper face of said base may beobtained, a block of polygonal section having a flat lower end adaptedto engage the upper face of the second ring and having a T-slotextending longitudinally of at least one side thereof perpendicular tosaid lower end, tenon means engageable in such last named T-slots and inone of the tenon slots in the upper face of said second ring to orientsaid block with respect to the tenon slots in the upper face of saidsecond ring, and means operable to secure the said block and said tworings to said base, with the angular relationship between the tenonslots and the two rings servings to determine the angular setting ofsaid block.

References Cited in the file of this patent UNITED STATES PATENTS2,006,262 Charvet June 25, 1934 2,201,454 Reich May 21, 1940 2,369,425Becker Feb. 13, 1945 2,676,413 Wharton Apr. 27, 1954 FOREIGN PATENTS913,752 France Sept. 19, 1946

1. A UNIT FOR USE IN CONSTRUCTING THE FRAME-WORK OF A JIG OR FIXTURE TOPOSITION A WORK-PIECE ABOVE A BASE HAVING A FLAT FACE FORMED WITH APLURALITY OF EQUALLY SPACED PARALLEL T-SLOTS EXTENDING LENGTHWISE IN THEUPPER FACE OF THE BASE, WHICH UNIT COMPRISES INTERCHANGEABLE RINGS EACHHAVING A FIRST TENON SLOT IN ITS UNDERFACE, TENON MEANS REMOVABLYENGAGEABLE IN A T-SLOT OF SAID BASE AND THE FIRST TENON SLOT OF ASELECTED RING FOR ORIENTING THE SELECTED RING WITH RESPECT TO A SLOT INTHE BASE, EACH RING ALSO HAVING A SECOND TENON SLOT IN ITS UPPER FACEDISPOSED AT A RESPECTIVE FIXED ANGLE TO SAID FIRST TENON SLOT, THE FIXEDANGLES OF RESPECTIVE RINGS DIFFERING FROM EACH OTHER, A BLOCK OFPOLYGONAL SECTION ADAPTED TO BE MOUNTED ON THE SELECTED RING ON THE BASEAND HAVING A FLAT LOWER END ENGAGEABLE WITH THE UPPER FACE OF THESELECTED RING, TENON MEANS OPERATIVELY ASSOCIATED WITH SAID BLOCK ANDENGAGEABLE IN SAID SECOND TENON SLOT OF THE SELECTED RING THEREBY TODETERMINE FIXEDLY THE ANGULAR RELATIONSHIP BETWEEN THE BLOCK AND THERING, AND MEANS FOR SECURING THE BLOCK AND THE SELECTED RING TO THEBASE.